Common Thresher Shark Classification:
| Kingdom | Animalia (animals) |
| Phylum | Chordata |
| Sub-Phylum | Vertebrata (vertebrates) |
| Class | Chondrichthyes (cartilaginous fish) |
| Subclass | Elasmobranchii (sharks and rays) |
| Order | Lamniformes |
| Family | Alopias |
| Genus | Alopias |
| Species | vulpinus |
General Description:
Thresher sharks are Lamniformes (or mackerel sharks) whose tail fin has a greatly elongated upper lobe. This tail can account for up to 50% of their overall length, this accounts for the fact that they are extremely strong swimmers who have been known to breach themselves completely out of the water.
Common threshers have a counter shaded body, dark blue-gray above and white underneath. It has small jaws, but can use its tail to corral and even kill fish. The first dorsal fin is much, much bigger than the second; the pectoral fins are curved. Like other mackerel sharks, it has an anal fin, 5-gill slits, 2 dorsal fins, no fin spines, mouth behind the eyes, and no nictitating eyelids. It is mostly nocturnal.
The Common Thresher shark ranges from 5 to 6 m long.

LOCATION
Although occasionally sighted in shallow, inshore waters, thresher sharks are primaril pelagic; they prefer the open ocean, staying within the first 500 m of the water column. Common threshers tend to be more common in coastal waters over the continental shelf of the North pacific, North America and Asia. They are rare in the Central and Western Pacific. More recently we have been lucky enough to be sighting these magnificent creatures right here.
TEETH AND DIET
The Thresher eats squid and fish, corralling them with its elongated tail, stunning them with slaps from it, and catching them with its very sharp (but small) teeth.
THRESHER SHARK ATTACKS
The Common Thresher Shark is not aggressive, but can be provoked. The thresher's large tail can injure divers.
REPRODUCTION
Threshers reproduce via aplacental viviparity, the eggs hatch inside the female. The developing embryos are ovophagous; they will eat smaller, weaker siblings while in the womb. Mature females 3 m long have litters of 4 to 6 pups, bearing live young. These pups are 1.1 to 1.5 m long at birth.
POPULATIONS
Sadly like all sharks, the Common Thresher is decreasing in numbers because of over fishing, it is hunted for meat and its fins but also by sports fishermen, for fun and trophy photographs!